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Sulfur is insoluble in water but sugar is soluble. Hence; dissolution of sugar to have sulfur as the only insoluble solid. Filtration: The filtrate is the liquid that passes through the filtration filter. Meanwhile, the residue is the solid that remains on the filtration filter. Evaporation: water as part of the filtrate changes into a gas to leave sugar as residue.

Freezing is a physical change. It involves a liquid changing states to a solid. Thus, freezing a substance will not change its chemical identity, but its state.

molar mass of water [7H\(_2\)O] = 7[ 2 * 1 + 16] → 7 * 18 = 126g/mol molar mass of ZnSO\(_4\).7H\(_2\)O = [65 * 1] + [32 * 1] + [16 * 4] + 7[ 2 * 1 + 16] → 65 + 32 + 64 + 126 = 287g/mol percentage of water of crystallization = \(\frac{mass of water of crystallization}{mass of hydrated compound} * 100%\) → \(\frac{126}{287} * 100\) = 43.9 ≈ 44%

1mole of gas at STP = 22.4dm\(^3\) 0.0075 mole of CaCO3 = xdm\(^3\) cross multiply; where 22.4dm\(^3\) = 22400cm\(^3\) x * 1 = 0.0075 * 22400 → 168cm\(^3\) the gas CO2 which evolved was gotten from CaCO3 so we use the number of moles of CaCO3 only

Sodium has atomic / proton number of 11 and belongs to Group 1[alkali metals] on the periodic table

The principal quantum number, n, describes the energy of an electron and the most probable distance of the electron from the nucleus. In other words, it refers to the size of the orbital and the energy level an electron is placed in. The azimuthal quantum number is a quantum number for an atomic orbital that determines its orbital angular momentum and describes the shape of the orbital.

\({Cu(NH_3)_4}^2\)+: The bonding in this ion consists of coordinate covalent bonds with all bonding electrons supplied by the nitrogen atom.

Potassium dichromate, K\(_2\)Cr\(_2\)O\(_7\) → [1 * 2] + [Cr * 2] + [-2 * 7] = 0 → 2 + 2Cr - 14 = 0 → 2Cr = 12 →Cr = \(\frac{12}{2}\) → 6

Gas pressure is the name given to the force exerted by gas particles colliding with the wall of their container.

An elastic collision is an encounter between two bodies in which the total kinetic energy of the two bodies remains the same.

Citric acid has 3 carboxyl groups, therefore, when reacts with NaOH, there is a simple salification reaction that will produce the trisodium citrate / sodium citrate. Trisodium citrate is a tribasic salt of citric acid. It is produced by complete neutralization of citric acid with high purity sodium hydroxide or carbonate and subsequent crystallization and dehydration.

krypton and xenon for high-speed pictures in a photographer's flash tube

efflorescence, spontaneous loss of water by a hydrated salt, e.g Sodium trioxocarbonate (IV) decahydrate \(Na_2CO_3. 10H_2O)\) also known as washing soda

The electrolyte is dilute sulfuric acid (= acidified water) which, during electrolysis is split into hydrogen and oxygen gases.

Electrolysis is used extensively in metallurgical processes, such as in extraction (electrowinning) or purification (electrorefining) of metals from ores or compounds and in deposition of metals from solution (electroplating). Copper is purified by electrolysis . Electricity is passed through solutions containing copper compounds, such as copper(II) sulfate.